Another possibility is that there is greater diversity in the US now than a hundred years ago, people are more aware of it, and are okay with it, so there's a much larger pool of names to choose from.

A hundred years ago, it would have been unthinkable for a white, English-speaking family to give their children a name that sounded even remotely non-Anglo-Saxon. Nowadays, nobody looks at you funny if you're named Mila or Declan.